Butt diode contacting



Nov. 17, 1970 R. TENENHOLTZ 3,541,430

BUTT DIODE CONTACTING Filed sepn.A so.' 1968 'Flai FIG. 2

INVENTOR. RDYBERT TENENHOLTZ United States Patent O 3,541,480 BUTT DIODE CONTACTING Robert Tenenholtz, Framingham, Mass., assignor to Sage Laboratories, Inc., Natick, Mass., a corporation of Massachusetts Filed Sept. 30, 1968, Ser. No. 763,576 Int. Cl. H01p I/00 U.S. Cl. S33-98 7 Claims ABSTRACT OF THE DISCLOSURE A spring loaded butt contact establishes good connection to a microwave diode electrode -while comprising an R-F bypass and a connecting link to the inner conductor of a low frequency coaxial output terminal pair.

BACKGROUND OF THE INVENTION The present invention relates in general to contacting high frequency diodes and more particularly concerns a novel means for establishing a good mechanical and electrical contact to the diode to enhance mechanical strength, reliability and reduce sensitivity to dimensional tolerances. The invention establishes positive electrical contacting under a wide variety of mechanical and environmental conditions while reducing costs and facilitating correct and easy replacement of diodes by unskilled personnel.

For many years resilient linger contacts have been used for connecting microwave diodes in coaxial and waveguide circuits. Although these contacts have performed reasonably well under normal circumstances, any deviation from ideal conditions, such as departure from mechanical tolerances, replacement by inexperienced technical personnel, unusual environmental conditions and the like can present problems. These prior art contacts typically are slotted, crimped and usually heat treated annular conductors of resilient material. The diode may then be snapped into place to be grasped by the finger contacts. In addition to the disadvantages enumerated above, one or more resilient ngers may be bent during diode replacement and possibly resulting in permanent damage.

Accordingly, it is an object of this invention to provide high frequency contacting that overcomes one or more of the disadvantages enumerated above.

It is a further object of the invention to provide microwave diode contacting that is stronger, more reliable and less critical with regard to dimension tolerances associated with diodes.

It is a further object of the invention to provide microwave diode contacting that provides positive electrical contact under a Wide variety of mechanical and environmental conditions Iwhile providing greater freedom from criticality in microwave circuit design.

It is a further object of the invention to achieve one or more of the preceding objects While reducing costs.

It is a further object of the invention to achieve one or more of the preceding objects while facilitating easy replacement of defective microwave diodes by unskilled personnel without reducing circuit performance.

It is still a further object of the invention to achieve one or more of the preceding objects with increased reliability.

SUMMARY OF THE INVENTION According to the invention, there is means for butt contacting at least one electrode of a high frequency diode. Preferably the invention comprises sprin g means for urging the butt contacting means against the diode electrode. According to a specific form of the invention the means for butt contacting comprises a conducting cylinder formed with an axially centered opening for snugly receiving a 3,541,480 Patented Nov. 17, 1970 ICC diode electrode and insulatedly separated from the outer coaxial conductor surrounding the microwave diode and the butt contact so that the latter also comprises an R-F bypass capacitor. Preferably a spring connected between an inner conductor connected to a low frequency coaxial output terminal pair and the butt contact urges the latter to make good mechanical and electrical contact with the microwave diode contact while electrically connecting the latter to the low frequency inner terminal. According to another form of the invention a low inductance assembly includes a spring seated inside a coaxial sleeve centered about the axis that acts on a piston attached to the butt contact.

Numerous other features, objects and advantages of the invention will become apparent from the following specilication when read in connection with the accompanying drawing in which:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a sectional viewthrough a typical spring loaded diode contacting arrangement according to the invention; and

FIG. 2 is a view of an alternate low inductance spring loaded diode contacting arrangement according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 'With reference now to the drawing and more particularly FIG. l thereof, there is shown a sectional view through an exemplary embodiment of a typical butt diode contacting arrangement according to the invention. Outer conductor 11 and inner conductor 12 may form the output terminal pair of a hybrid or other device in which there is microwave energy between inner conductor 12 and outer conductor 11. Inner conductor 12 is formed with a recess 13 for snugly accommodating electrode 14 of microwave diode 15. The other electrode 16 of microwave diode 15 snugly rests in butt vcontact with the opening 21 of cylindrical butt contact 22 that is insulatedly separated from outer conductor 20 by an insulating sleeve 23 so that butt contacting element 22, outer conductor 20` and insulating sleeve 23 form an R-F bypass capacitor. Insulating sleeve 23 thus prevents and allows radial and axial movement respectively of cylindrical butt contact 22. A spring 24 urges butt contact 22 rmly against electrode 16 of diode 15 and urges diode 15 against inner conductor 12 so that the other diode electrode 14 snugly engages inner conductor 12 in butt contacting relationship. The right end of spring 24 is connected to stud 25 attached to low frequency inner conductor 26 that comprises the inner terminal of low frequency output coaxial terminal pair 27. Inner conductor 26 is seated within an insulating sleeve 29 that in turn snugly tits within outer conductor 2,8. Outer conducting sleeve 20 is conveniently internally threaded at both ends as shown so that it may screw on the externally threaded outer conductor 11 and receive the externally threaded outer conductor 28.

Inserting or replacing a microwave diode is extremely simple. Outer conductor 20 is unscrewed, an electrode 14 of a new diode 15 is inserted in recess 13, and outer conductor 20 screwed on over outer conductor 11. Electrode 16 automatically seats in recess 21. The diode will be properly and securely positioned from both mechanical and electrical Viewpoints.

Referring t0 FIG. 2, there is shown an alternate spring arrangement in which a conducting sleeve 31 carries spring 24. Spring 24 acts on a piston 32 soldered to butt Contact 22. The other end of sleeve 31 ts snugly on stud 25 attached to inner conductor 26. This assembly is characterized by exceptionally low inductance.

There has been described novel butt contacting meansY characterized by excellent mechanical and electrical contacting, insensitivity to mechanical variations and environmental conditions, ease of replacement, ease of manufacture, low cost and high reliability. It is evident that those skilled in the art may now make numerous uses and modifications of and departures from the specific embodiments and techniques described herein without departing from the inventive concepts. Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in or possessed by the apparatus and techniques herein disclosed.

What is claimed is:

1. High frequency device butt contacting structure comprising,

means dening a cylindrical conducting plug,

means dening a conducting housing normally maintained at reference potential,

annular"sleeve means for insulatedly supporting said conducting plug within said conducting housing to allow and prevent axial and radial movement respectively of said plug within said housing and coacting therewith to form a bypass capacitance from said plug to said housing,

said conducting plug being formed with an opening for snugly receiving a device terminal in butting mechanical and electrical contacting relationship,

and spring means insulatedly separated from and within said conducting housing for urging said conducting plug against a microwave device terminal.

2. High frequency device butt contacting structure in accordance with claim 1 and further comprising,

a low frequency coaxial output terminal pair having an inner terminal connected by means including said spring means to said conducting plug and Yan outer conductor connected to said conducting housing.

3. High frequency device butt contacting apparatus in accordance with claim 2 wherein said recess in said conducting plug embraces the axis of said inner conductor.v

4. High frequency device butt contacting structure in accordance with claim 3 and further comprising a conducting sleeve surrounding said spring means and contacting said inner conductor and supporting a piston urged against said conducting plug by said spring means to comprise a low inductance connection between said conducting plug and said inner conductor. v

5. High frequency device butt contacting apparatus in accordance with claim 3 and further comprising,

another coaxial terminal pair having an outer conductor and an inner conductor formed with a second recess for receiving another electrode of a device.

6. High frequency device butt contacting apparatus in accordance with claim 5 and further comprising said device,

said device being` a microwave diode having a pair of inline electrodes seated in` respective ones of said recesses to coaxially mount said diode intercoupling said recesses in rectifying contact.

7. High frequency device butt contacting structure comprising,

means dening the outerconductor of a coaxial line,

and central means coacting with the outer conductor to form a coaxial line,

the central means comprising a conductive sleeve surrounding spring means in contacting relationship with a coaxial line center conductor stud and supporting a piston urged away from the stud by the spring means to comprise a low inductance connection between the piston and the stud.

A References Cited UNITED STATES PATENTS 2,642,494 6/ 1953 Zaslavsky et al. 329--162 X 2,810,829 10/ 1957 Schrock 329-162 2,894,229 7/ 1959 Fonda-Bonardi 3'33-98 3,002,155 9/ 1961 Dees 329--162 3,079,564 2/ 1963 Bogle et al 329-162 3,191,125 6/1965 Hunton et al 333-98 X HERMAN KARL SAALBACH, Primary Examiner S. CHA'IMON, JR., Assistant Examiner U.s. c1. X.R. 317-236; 329-162; S33- 1s 

